icyphox / asdf Goto Github PK

Nice article, thanks for sharing it. 😉

By the way, in the article you say:

I’m not sure why it uses puts here? I might be missing something; perhaps printf calls puts.

That's actually a gcc "optimization": as your code does not use any formatting feature from printf function (%d, %s, etc with runtime-dependant values) it can be replaced by the simpler puts, which is cheaper call.

You can disable that using the gcc -fno-builtin-printf option:

$ gcc -o chall.elf chall.c
$ nm chall.elf | grep -E puts
                 U puts@@GLIBC_2.2.5

$ gcc -fno-builtin-printf -o chall.elf chall.c
$ nm chall.elf | grep puts
$

Sorry about opening an issue here. There's no issue with your code/article but I found it the easiest way to contact you regarding this.

Ciao!